benz canpark system?

hello everyone. i am having trouble with an install i have done recently. It was on an 09 Merc Benz SL63 AMG where i had installed a K40 unit with the diffusers added, as well as the addition of 2 autopage bps-4 systems (one up front and one in reverse).

I have the front sensors and k40 equiptment on a switched ignition source and the rear sensors and k40 equiptment ran to the battery in the trunk, althought the bps-4 is set to come on via the reverse wire. Everything acts great until you go to put the system in reverse and test those sensors. When in reverse the bps-4 beeps almost continuous like you are a few inchs from hitting an obstacle. Both front and rear sensors are painted to match the vehicle, and autopage tech support thinks its because the sensors are painted. The front act fine and i have installed a few of these system and paint em all without problems.

I was thinking maybe it is the k40 and bps-4 both interfering with the others radio signal. K40 tech support says they are a send and recieve unit only so if thier product isnt actting up then there is no interference between them. my boss seems to think that the systems dont act up in reverse but when the brake pedal is pressed on (and ofcourse you press the brake to shift into R). He has done a lil research and seems to think the canpark system on the car is whats creating the problem. I ordered that part incase i need it even tho its not guarenteed to be compatible with the 09, only up to 08. The car is at the MB dealership now and i will get it back soon. i havent had the time to test my bosses theory of the park OR reverse causing problem. I just want opinions on what you would do to troubleshoot so when i have it i can have a gameplan.

When i get to have car back i plan to isolate the front and reverse bps-4 systems from coming on simultaniously with a relay. possibly use dif ground points for all dif units. dif power supplies if needed and of course the canpark if all else fails. just brainstorm and throw me any suggestions cuz its hard to find answers on a $145,000 car thats only been out for 6 months

This has HowieII written all over it.  he's the man with German Vehicles.....you might want to PM him and try and pick his brain. 

make sure you use your english accent....  ; )

the canpark piece worked out although im not sure if i needed it after all. we got our poer source from an unused source in the fuse box (there is a male spade between the 2 major fuse lines that is an acc source, with a female and a good eye you can slide right in there). well for what ever reason we got alot of backfeed when the k40 and parking sensors were both connected to same power source. we found another switched power and it actted better but then you put car back and it would act up again. after chasing ghosts we realized this car has a magnetic field or something in the fuse box area. anything you mount in that area will pick up backfeed!! hope this helps if any of you come across this devil of a car.\

back to the can park system... it works with the car without any problems but im not sure if i really needed it. after i found out about the fuse box area i wasnt about to try n take out canpark to see if it was neccesary. i knew the car had a backfeeed prob but i thought if i tap into can system it would help. so i dont think it helped at all with that problem, but it does have a 12v output between 1 and 6 mph and 12v out when in reverse. is it worth the $200? prob not but i we charged the guy enough to make it worth our while